import math

def quadratic(a, b, c):
	tmp = b*b - 4*a*c
	if tmp < 0:
		return False
	#记得小括号要添上，即使知道优先级，最好也添上
	x1 = (-b + math.sqrt(tmp)) / (2*a)
	x2 = (-b - math.sqrt(tmp)) / (2*a)
	
	return x1, x2
	
print(quadratic(2, 3, 1))
print(quadratic(1, 3, -4))